Em Thu, Oct 30, 2014 at 09:43:59AM +0100, Peter Zijlstra escreveu: > On Fri, Oct 24, 2014 at 10:44:54AM +0300, Alexander Shishkin wrote: > > Peter Zijlstra <[email protected]> writes: > > > On Mon, Oct 13, 2014 at 04:45:46PM +0300, Alexander Shishkin wrote: > > >> When a new event is inherited from a per-task kernel event that has a > > >> ring buffer, allocate a new buffer for this event so that data from the > > >> child task is collected and can later be retrieved for sample annotation > > >> or core dump inclusion. This ring buffer is released when the event is > > >> freed, for example, when the child task exits.
> > > This causes a pinned memory explosion, not at all nice that. > > > I think I see why and all, but it would be ever so good to not have to > > > allocate so much memory. > > Are there any controls we could use to limit such memory usage? > I'd say the same limit we're already accounting the mmap()s against. But > the question is; what do we do when we run out? > Will we fail clone()? That might 'surprise' quite a few people, that > their application won't work when profiled. Can't we just emit PERF_RECORD_THROTTLE or similar stuff then? I.e. somehow mark the cloned process as not being profiled due to ENOMEM? - Arnaldo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
